Mobile phone giant Vodafone has unveiled a 5.7% rise in operating profits as it said chief executive Arun Sarin would step down at the end of July.

Mr Sarin leaves after five years in charge and will hand over the reins to deputy chief executive Vittorio Colao.

The news came as Vodafone reported its full-year figures, revealing adjusted operating profits of £10.1 billion for the 12 months to March 31. Underlying pre-tax profits rose 2% to £8.93 billion, according to the group.

Vodafone chairman Sir John Bond paid tribute to Mr Sarin and the "tremendous" job he has done during his tenure. He said: "He has led the company with distinction and navigated Vodafone through a period of rapid change."

Indian-born Mr Sarin, 53, joined Vodafone's board in 1999 and became chief executive in July 2003. He went through a rocky patch two years ago, when nearly 10% of Vodafone shareholders voted against his re-election as chief executive.

But the company has since outperformed City profit forecasts and enjoyed big revenue growth in fast-growing markets such as India and Turkey.

In January Vodafone, whose headquarters are in Newbury, Berkshire, revealed that the majority of its customers are now outside western Europe.

Mr Sarin also helped steer the group through the aftermath of the dotcom crash and has over the past five years boosted the firm's customer base from 120 million to 260 million globally.

Mr Sarin said: "It has been a privilege to lead Vodafone for the last five years and to have been involved in the company for such a long time.

"I feel that I have accomplished what I set out to achieve, particularly in developing and implementing a new strategy. I am very proud of what Vodafone and its 71,000 people have achieved and the good momentum we have in the marketplace.

"I know that the business is in capable hands with Vittorio Colao. Having worked with him for many years I know that he has the experience and vision to take Vodafone on to future success."